Transcript for Friend of Boston Bombing Suspect Shot and Killed by FBI Agent

And other terror investigation right here at home the Boston bombings and the two Brothers allegedly forming their own terror cell. And the man who may have hold clues to who they -- tonight has been shot. By the FB IA BC's senior justice correspondent Pierre Thomas has those details. Abraham Thomas -- have a mixed martial arts writer was friends with suspected marathon farmer -- Oman -- Even trained at the same gym that -- always leaving Boston -- The island they stand -- not hang -- he knew of because there was a blemish -- there wasn't -- -- -- was -- boxer. The FBI had been talking to -- him -- -- in for weeks after the discovered he had called Tamil on the days before the bombing. Early this morning authorities were interviewing tarnish when matters turned violent law enforcement sources say he lunged at an FBI agent with the night. He was shot and killed. In a dramatic twist sources tell ABC news -- I was about to sign a confession. In connection with a 2011 triple homicide in the Boston area. Three men had their throats slashed marijuana and cash sprinkled over their bodies. System Boston bombings Tamil on the new younger brother Joseph -- have emerged as key suspects in those legs. The victims were associates of tarnish him and Cameroon law enforcement sources say there's no evidence so far -- -- him. To the bombings. Pierre Thomas ABC news Washington.

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